Topologically close-packed phases: Deposition and formation mechanism of metastable β-W in thin films
Abstract
β-W is a metastable, topologically close-packed phase with the A15 structure. The deposition of β-W, using N2 as the impurity gas introduced into the sputtering chamber, is reported and a mechanism for β-W formation is proposed. Molecules of the impurity gas in the chamber are adsorbed onto the surface during the deposition process and act as nucleation sites for the formation of β-W. The proposed mechanism is supported by the dependence of β-W phase fraction in sputter deposited films on pressure of N2 and on substrate temperature.
- Publication:
-
Acta Materialia
- Pub Date:
- February 2016
- DOI:
- 10.1016/j.actamat.2015.11.049
- Bibcode:
- 2016AcMat.104..223L
- Keywords:
-
- β-W;
- Nucleation;
- Adsorption;
- Thin films;
- Metastable phases